Tracked military vehicle capable of high speeds, e.g. speeds in excess of 30 miles per hour, are susceptible to catastrophic destruction on the occurrence of track loss, whether from connector pin failure, linkage failure, or guide system failure. Vehicle stability and control suffers greatly, especially if only one track is separated (lost) from the vehicle. In such a case, the rolling resistance of the vehicle on the "lost track" side is suddenly reduced. Additionally, the still-operable track continues to receive power, thereby tending to decrease the effective driving force to the other side of the vehicle. Depending on vehicle mass, inertia and the nature of the terrain, the untracked side may decelerate at a faster or slower rate than the tracked side. The vehicle thus tends to swerve and possibly even roll over rather than coming to a straight stop. The swerving condition is especially dangerous at high speeds when the vehicle may entirely lose a track within a time interval of one second or less, usually before the driver is aware of the dangerous condition.
The present invention proposes an emergency brake system that is automatically triggered by loss or separation of one or both tracks. One or more track-loss sensors produce braking actions at the road wheels and/or at skid rams carried on the vehicle. Preferably the braking action is modulated or pulsed so that braking pressure is directed to the faster moving road wheels, thereby tending to prevent skidding of the wheels or swerving of the vehicle.
The track-loss sensors also preferably act as triggering devices for a "driver override" system that automatically cuts out the conventional manual sprocket brake, manual shift, and manual steer.